diff --git a/Library/Homebrew/cask/audit.rb b/Library/Homebrew/cask/audit.rb
index d365b5b77b..080bc6f109 100644
--- a/Library/Homebrew/cask/audit.rb
+++ b/Library/Homebrew/cask/audit.rb
@@ -27,15 +27,15 @@ module Cask
                    new_cask: nil)
 
       # `new_cask` implies `online` and `strict`
-      online = new_cask if online.blank?
-      strict = new_cask if strict.blank?
+      online = new_cask if online.nil?
+      strict = new_cask if strict.nil?
 
       # `online` implies `appcast` and `download`
-      appcast = online if appcast.nil? # `appcast` is `nil` if neither `--appcast` nor `--no-appcast` are passed
-      download = online if download.blank?
+      appcast = online if appcast.nil?
+      download = online if download.nil?
 
       # `new_cask` implies `token_conflicts`
-      token_conflicts = new_cask if token_conflicts.blank?
+      token_conflicts = new_cask if token_conflicts.nil?
 
       @cask = cask
       @appcast = appcast
diff --git a/Library/Homebrew/dev-cmd/audit.rb b/Library/Homebrew/dev-cmd/audit.rb
index 1f58971355..5ca4cb4f78 100644
--- a/Library/Homebrew/dev-cmd/audit.rb
+++ b/Library/Homebrew/dev-cmd/audit.rb
@@ -206,14 +206,17 @@ module Homebrew
       require "cask/cmd/abstract_command"
       require "cask/cmd/audit"
 
+      # For switches, we add `|| nil` so that `nil` will be passed instead of `false` if they aren't set.
+      # This way, we can distinguish between "not set" and "set to false".
       Cask::Cmd::Audit.audit_casks(
         *audit_casks,
         download:              nil,
+        # No need for `|| nil` because this is a `--[no-]appcast` and automatically sets itself to `nil` if not passed
         appcast:               args.appcast?,
-        online:                args.online?,
-        strict:                args.strict?,
-        new_cask:              args.new_cask?,
-        token_conflicts:       args.token_conflicts?,
+        online:                args.online? || nil,
+        strict:                args.strict? || nil,
+        new_cask:              args.new_cask? || nil,
+        token_conflicts:       args.token_conflicts? || nil,
         quarantine:            nil,
         any_named_args:        !no_named_args,
         language:              nil,